Gantry cranes

ABSTRACT

A movable gantry crane for erecting a wide span structure comprising several bridge-like sub-structures arranged side by side in spaced relationship, which crane comprises: a horizontal girder long enough to span the structure and supported at each side of the structure by movable support columns; a platform suspended from the girder from hangers so as to lie beneath a sub-structure to be erected and enable work to be carried on without interference with the area spanned by the structure; there being at least one set of hangers in front of this substructure, and at least one other set of hangers behind it and which can be displaced to permit the crane and the platform to be moved forward when the sub-structure has attained a stable condition; and a lifting device movable along the girder between the sets of hangers.

[451 Feb.4, 1975 United States Patent [191 Dobbie et al.

1 GANTRY CRANES 3,699,688 29/429 1/1974Stewart........,........................212/14 r a p S t r e b O R r e mm m 8 E m W a 8 m n 3 P mm mm e0 hb 6! .mm W0 am: 0 a D mm .mW m H Md mpw rnl fl h n CJE r O t n e v ..m H 7 k a .W D. .S r e h ..m P. n b. V.am 6 m 1m F mm r a e i .mmM m & XA E m mm l .mmC SIC t AA M V na m n 0darn n LO-" a 8 l mm aw a .1 61B .0 uf ud i en.lw 00 H ma flhilo h mT wnlM spa .cw uuEm m m "MP Se ar. khflw Q S Mm Mm .l oil C PI. H 6 6 n g Ms A ABSTRACT [22] Filed: Dec. 6, 1973 A movable gantry crane forerecting a wide span structure comprising several bridge-likesub-structures arranged side by side in spaced relationship, which cranecomprises: a horizontal girder long enough to span the structure andsupported at each side of the structure by movable support columns; aplatform suspended from the girder from hangers so as to lie beneath asub-structure to be erected and enable work to be carried on withoutinterference with the area spanned by the structure; there being atleast one set of hangers in front of this sub-structure, and at leastone other set of hangers behind it and which can be displaced to permitthe crane and the platform to be moved forward when the sub-structurehas attained a stable condition; and a lifting device movable along thegirder between the sets of hangers.

2 30 3 4 H wnmmzmn Mm 449 ,44 W0133 a 6 4 29., 5 7 1M3 9 .22 7 u 3 l m.m mu haw a m 4 ll S D m m d- M w 5 W M E m mu M 5 l n n 1 "1N4 P m 2w m,H m P H m 5% m w m m mm 3 a a m m v n m. m mm m W mfl a D. a m 6 I n D.m mm). 4 A U m E .2 u 855 n 7 -H2 I 0 H m N N r .l. o 8 C U 2 U m. F umD. n 5 MR l l. l. ll l 0 2 00 6 2 3 5 55 5 2,554,768 5/1951 Allen 29/4317 Claims, 5 Drawing Figures PATENTED FEB 4!.975

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l GANT RY CRANES This invention relates to gantry cranes useful in theerection of structures which comprise several bridgelike sub-structuresarranged side by side in spaced relationship. Such a structure may berequired, for example, for covering a railway goods yard. In such a casethe bridge-like sub-structures span the full width of the goods yardwithout intermediate supports and are disposed side by side along thelength of the goods yard at a spacing appropriate for carryingload-supporting flooring or the like between them. Buildings or the likemay be erected on the structure to afford an additional use for thegoods yard site. Another example of such a structure is a bridge over ariver or motorway.

The erection of the bridge-like sub-structures requires the emplacementof massive structural elements such as blocks orbeams of pre-stressedconcrete. This can be accomplished by means of a giant gantry cranewhich spans the structure, the supporting columns being disposed beyondthe ends of the bridge-like substructures and these columns beingthemselves movable on rails or prepared tracks so that the whole cranecan be moved forwards as the bridge-like substructures are progressivelycompleted to a condition in which they are self-supporting and laterallystable.-

According to the present invention a movable gantry crane useful in theerection of such a structure comprises a girder long enough to span thestructure, supported by movable supporting columns, at least two sets ofhangers which suspend a platform from the girder in a position to liebeneath a bridge-like substructure to be erected with the aid of thecrane, at least one set being disposed to occupy a position in front ofthe said sub-structure and at least one other set being disposed tooccupy a position to the rear of the said sub-structure, a liftingdevice movable along the girder between sets of hangers disposed tooccupy positions respectively in front of and to the rear of the saidsubstructure, and the hangers of the said other set or sets beingremovable or displaceable to permit the crane including the platform tobe moved forwards when this sub-structure has been made self-supportingand laterally stable.

The provision of the platform beneath the substructure which is beingerected with the aid of the crane enables the erection work to becarried on without risk of articles or material employed in the erectionfalling to the ground if accidentally dropped. Thus the movement ofpersons or vehicles at ground level can continue safely and withoutinterruption throughout the construction of the whole structure, whichmay extend over a long period of time. Also, the platform enables theconstruction work to be carried on without the erection of temporaryscaffolding from ground level. However, the presence ofplatform-supporting hangers behind the sub-structure being erected wouldprevent the crane from being moved forward, unless these hangers areremovable or displaceable. By making these hangers capable of beingremoved or displaced, the crane can be moved forward together with theplatform when a sub-structure has reached a selfsupporting and laterallystable condition, so that the erection of the next sub-structure can becommenced. The hangers positioned in front of the sub-structure beingerected need not be removable or displaceable because these hangers donot interfere with the forward movement of the crane. Of course,temporary supports for the rear portion of the platform must be providedwhen the removable or displaceable hangers are removed or displaced.These temporary supports could be a further set of removable ordisplaceable hangers disposed further to the rear and which would remainin position until the crane had been moved forward and the removed ordisplaced set had been repositioned in front of the newly erectedsub-structure. This further set would then be removed or displaced topermit further forward movement of the crane.

There may be another lifting device movable along the girder to the rearof the set or sets of removable or displaceable hangers.

Preferably the platform is long enough to encompass three sub-strctures.In this case the crane may have a forward working bay served by thefirst-mentioned lifting device for the erection of the foremostsubstructure and a rear working bay served by the said other liftingdevice for operations between the two previously erected sub-structures.Thus, while the forward sub-structure is being erected in the forwardbay, further work may be carried out between the next two previouslyerected sub-structures in the rear bay.

The sequence of erection may be as follows: 1. The crane is movedforwards to a new position. 2. Construction units for the newsub-structure are brought to the site and hoisted into position, alignedand then jointed,

in the forward bay of the crane. In the rear bay, floor and wall unitsare erected between and upon the two previously erected sub-structures,and temporary stabilising beams connecting these two sub-structures areremoved. 3. Stressing cables are threaded and joints cured in thesub-structure in the forward bay, and after curing the cables arestressed. The construction work may continue in the rear bay. 4.Temporary beams are erected between the newly erected sub-structure inthe forward bay and the adjacent previously completed sub-structure inthe rear bay, to stabilise the new substructure laterally. Theconstruction work in the rear bay is completed. 5. The crane is movedforwards to the next position.

The said previously erected sub-structure, being in a self-supportingand laterally stable condition, can serve as a temporary support for theplatform. For example, the platform may be suspended from thissub-structure on roller supports, to enable the platform to move forwardfreely relative to these supports. The platform extends still further tothe rear, at least as far as the next previously erected sub-structure,from which it can be supported in a like manner. This enables theconstruction of the permanent load-supporting flooring between the twocompleted sub-structures to be carried on safely and easily.

One or both ends of the girder of the gantry may project beyond therespective supporting column or columns so that the movable liftingdevice or devices supported by the girder can pick up loads from aposition beyond the column or columns and carry these loads along thegirder to the point of use.

The invention may be performed in various ways and a specific embodimentwill now be described by way of example with reference to theaccompanying somewhat diagrammatic drawings, in which:

FIG. 1 is an overhead perspective view of a structure for the erectionof which a gantry crane embodying the invention is used;

FIG. 2 is a perspective view of a gantry crane embodying the inventionbeing used in the erection of parts of the structure shown in FIG. 1;

FIG. 3 is a front elevation of the crane and parts of the structurebeing erected; I

FIG. 4 is a side elevation of the crane and part of the structure,looking from the left in FIG. 3; and

FIG. 5 is a side elevation of portions of the crane and of thestructure, partly in section.

Referring to FIG. 1, there is shown a structure which comprises severalbroad span bridge-like substructures lla 11k arranged side by side inspaced relationship. The structure 10 covers an area 12, such as arailway goods yard or a multi-lane highway. Extending between thesub-structures 11a 11k is loadsupporting flooring 13, and on this thereare buildings 14. The whole structure 10 is erected in a mannerdescribed below which enables the area .12 to remain in use throughoutthe whole period of construction, without risk of articles or materialsemployed in the construction falling to the ground if accidentallydropped, and without obstruction by the erection of temporaryscaffolding from ground level.

For the erection of the structure 10 a giant gantry crane (FIGS. 2 to 5)is employed. This comprises two supporting columns 21 and 22 and agirder 23. Each of the supporting columns comprises a pair of towers 24,25 and 26, 27, respectively, spacing girders 28 and 29 between thebottoms of each pair of towers, and cross beams 30 and 3l at the tops ofeach pair of towers. Each tower is mounted on a wheeled or tracked bogie32 which is movable on rails or prepared trackways 33 beside the area12. The towers are connected by pin joints 34 to the bogies 32, tofacilitate erection of the crane and adjustment of the verticalpositioning of the supporting columns. The cross beams 30 and 31 areconnected to the. tops ofthe towers by pin joints 35, also to facilitateerection of the crane. The towers 24-27 are built up from bracedsections which are bolted together end to end on the site, in the mannerof conventional tower cranes. The girder 23 is also built up from bracedsections bolted together, but as can best be seen in FIGS. 2, 4 and 5there are front sections 36 and rear sections 37, the forward sections36 being narrower than the rear sections 37. The front sections 36 areprovided with tracks or rails 38 supporting a crab 39 with lifting gear40. The crab 39 is movable along these rails for the whole length of thegirder 23. A monorail 41 is provided at the rear of the sections 37,which supports movable lifting equipment 42. The ends of the girder 23project outwards beyond the support ing columns 21 and 22 so that whenthe crab 39 or the lifting equipment 42 is moved to either end of thegirder its hook or other load-supporting device can be lowered to pickup structural elements or constructional materials from beside the railsor trackways 33 on which the crane is supported, and lift and carrythese elements or materials to the point of use between the supportingcolumns.

The crane has a forward working bay 70 served by the crab 39 and a rearworking bay served by the lifting equipment 42.

The crane can be erected by assembling the towers on the bogies on thesite, these being held vertical by temporary struts 45 equipped withadjusting devices 46 (FIG. 2). The girder 23 can be erected in twohalves in a vertical position, one half on each side of the area l2,

between the respective towers 24, 25 and 26, 27. The cross beams 30 and31 are attached to the girder halves, in a position turned through fromthat in which they are shown in the drawings, and joined to the tops ofthe respective towers by only one set of the pin joints 35. The halvesof the girder are then swung up to a horizontal position, with the crossbeams pivoting on the towers about the already fitted pin joints 35. Thestruts 45 are adjusted to hold the towers somewhat outwardly from thevertical until the two inner ends of the girder halves are properlyaligned. The adjusting devices 46 are then eased to allow the said twoends to meet so that they can be bolted together. The remaining pinjoints 35 are then fitted,

Attached to the front lower beam 49 of the girder 23, near the frontcrab rail 38, is a set of hangers 50. These are termed herein permanenthangers because they can remain in place throughout the erection of thestructure 10 in contrast to displaceable hangers 51 and 52 referred tobelow. The permanent hangers 50 may be rigid tubes, for example.

Attached to another lower beam 53 of the girder 23, near the rear crabrail 38, is a first set of displaceable hangers 51, while attached to alower beam 54 of the girder 23 intermediate between the beam 53 and themonorail 41 is a second set of displaceable hangers 52.

Suspended from the hangers 50, 51 and 52 is a platform 55. This platformis shaped and disposed so as to lie just beneath the bridge-likesub-structures 11 and to span the area 12 from side to side. As bestseen in FIGS. 4 and 5, the platform is long enough to extend beneaththree sub-structures, in the case illustrated in these FIGS. thesub-structures 11d, lle and 11f The forward end of the platform issomewhat ahead of the set of permanent hangers 50 which are attached tothe platform by suitable fasteners 56. In contrast, the rear portion ofthe platform extends for some distance beyond the second set oftemporary hangers 52, and to assist in supporting this portion of theplatform the rear two 11d and lle of the three sub-structures overlyingthe platform are provided temporarily with rollers 57 and 58,respectively, which engage longitudinal members 59 of the platform (FIG.5). The temporary hangers 51 and 52 are attached to the platform byreleasable fasteners 61 and 62, respectively, and these hangers alsoinclude jacks or tensioning devices 63 and 64, respectively.

The method of using the crane will now be described. Let it be assumedthat starting from the left or far end of the structure 10 in FIG. 1,the structure has been erected and provided with load-supportingflooring 13 as far as the sub-structure 11d. The adjacent substructurelle has been erected and braced against the sub-structure 11d bytemporary stabilising beams 66 (FIG. 5). The next sub-structure Ilfis inthe course of erection. The crane is in the position in which it isshown in FIGS. 4 and 5. The platform 55 lies beneath the two completedsubstructures 11d, lle and beneath the foremost substructure llfwhich isin course of erection. There is no need for the platform to extend anyfurther back than the sub-structure 11d because the load-supportingfloor 13 is already in place behind this sub-structure. Betweensub-structures 11d and I 1e, however, the platform 55 is necessary sothat work can be carried out between these sub-structures, e.g., for theconstruction of a section of load-supporting flooring between them,without risk of any articles or material falling into the area 12. Thiswork is carried out with the aid of the lifting equipment 42 in the rearbay 71 of the crane. The sub-structure 11f is erected in the front bay70 of the crane with the aid of the crab 39 and its lifting gear 40. Theplatform also underlies the front bay 70. In the front bay 70,structural elements 72 for the sub-structure 11 f are hoisted intoposition by the crab 39 and its lifting gear 40, aligned and thenjointed. In the rear bay 71, units to form the floor 13a are placedbetween the sub-structures 11d and lle, whereupon the temporarystabilising beams 66 are removed. Wall units are also erected in thisbay. in the front bay 70, stressing cables are threaded and joints curedin the sub-structure 11f, and after curing the cables are stressed. Theconstruction work may continue simultaneously in the rear bay. Next, thetemporary stabilising beams 66 are placed between the substructure lle,now stabilised by permanent connexion to the sub-structure lld oncompletion ofthe floor 13a, and the newly completed sub-structure 11f,and the construction work in the rear bay 71 is completed. The crane nowhas to be moved forwards by a distance equal to the spacing of thesub-structures so that the next sub-structure 11g can be erected andflooring and other work can be carried on between the substructures lleand 11f. This forward movement of the crane is accomplished as follows.

The jacks 63 for the first set of displaceable hangers 51 are slackedoff and the fasteners 61 at the lower ends of these hangers arereleased. These hangers can now be hitched up to clear the sub-structurellfas the crane is moved forward along the rails or trackways 33. Whenthe hangers 51 have passed over the substructure llfi but before thesecond row of displaceable hangers 52 have reached the sub-structurellfthe fasteners 61 are re-connected and the jacks 63 tightened totension the hangers 51. Also, the jacks 64 for the second set ofdisplaceable hangers 52 are slacked off, the fasteners 62 are releasedand the hangers 52 are hitched up to clear the sub-structure llfas thecrane is moved further forward to its new working position. The rollers58 which supported the rear portion of the platform 55 on thesub-structure 11d may be removed when the platform has moved away fromthese rollers, and they. are then fitted to the sub-structure 11).

The displaceable hangers 51 and 52 need not be cables, as so fardescribed. For example, they may consist of upright lattice panels eachhaving a foldable hinged portion which can be swung out of the way ofthe substructures as the crane is being moved forward, or each of thepanels could have a separate removable portion which is bolted in placewhen the crane is in a working position.

The girder 23 may be given an upward camber in its unloaded condition,such that when it is under load it is straight and horizontal.

There may be pin joints 68 near the tops of the towers of one of thesupporting columns to prevent flexure of the girder 23 imposing bendingforces on the columns see HO. 3).

What we claim as our invention and desire to secure by Letters Patentis:

l. A movable gantry crane useful in the erection of a structurecomprising several bridge-like substructures arranged side by side inspaced relationship; which crane comprises a girder long enough to spanthe structure. supported by movable supporting columns, at least twosets of hangers which suspend a platform from the girder in a positionto lie beneath a bridge-like sub-structure to be erected with the aid ofthe crane, at least one set being disposed to occupy a position in frontof the said sub-structure and at least one other set being disposed tooccupy a position to the rear of the said sub-structure, a liftingdevice movable along the girder between sets of hangers disposed tooccupy positions respectively in front of and to the rear of the saidsub-structure, and the hangers of the said other set or sets beingremovable or displaceable to permit the crane including the platform tobe moved forwards when this sub-structure has been made self-supportingand laterally stable.

2. A gantry crane as claimed in claim 1 in which there is one set ofhangers disposed to occupy a position in front of the said sub-structureand two sets of removable or displaceable hangers disposed to occupypositions to the rear of the said sub-structure at different distancestherefrom sub-structure, said two sets being disposed at differentdistances rearwardly from said last-mentioned sub-structure.

3. A gantry crane as claimed in claim 1 in which there is anotherlifting device movable along said girder to the rear of said at leastone other set of hangers.

4. A gantry crane as claimed in claim 1 in which said platform is longenough to encompass three of said substructures.

5. A gantry crane as claimed in claim 4 in which there is anotherlifting device movable along said girder to the rear of said at leastone other set of hangers and said crane has a forward working bay servedby said first-mentioned movable lifting device and a rear working bayserved by said other movable lifting device.

6. A gantry crane as claimed in claim 4 in which said platform isadapted to co-operate with roller supports therefor mounted on at leastone of said sub-structures which is in a self-supporting and laterallystable condition.

7. A gantry crane as claimed in claim 1 in which at least one end ofsaid girder projects beyond the respective supporting column.

1. A movable gantry crane useful in the erection of a structurecomprising several bridge-like sub-structures arranged side by side inspaced relationship; which crane comprises a girder long enough to spanthe structure, supported by movable supporting columns, at least twosets of hangers which suspend a platform from the girder in a positionto lie beneath a bridge-like substructure to be erected with the aid ofthe crane, at least one set being disposed to occupy a position in frontof the said substructure and at least one other set being disposed tooccupy a position to the rear of the said sub-structure, a liftingdevice movable along the girder between sets of hangers disposed tooccupy positions respectively in front of and to the rear of the saidsub-structure, and the hangers of the said other set or sets beingremovable or displaceable to permit the crane including the platform tobe moved forwards when this suB-structure has been made self-supportingand laterally stable.
 2. A gantry crane as claimed in claim 1 in whichthere is one set of hangers disposed to occupy a position in front ofthe said sub-structure and two sets of removable or displaceable hangersdisposed to occupy positions to the rear of the said sub-structure atdifferent distances therefrom sub-structure, said two sets beingdisposed at different distances rearwardly from said last-mentionedsub-structure.
 3. A gantry crane as claimed in claim 1 in which there isanother lifting device movable along said girder to the rear of said atleast one other set of hangers.
 4. A gantry crane as claimed in claim 1in which said platform is long enough to encompass three of saidsub-structures.
 5. A gantry crane as claimed in claim 4 in which thereis another lifting device movable along said girder to the rear of saidat least one other set of hangers and said crane has a forward workingbay served by said first-mentioned movable lifting device and a rearworking bay served by said other movable lifting device.
 6. A gantrycrane as claimed in claim 4 in which said platform is adapted toco-operate with roller supports therefor mounted on at least one of saidsub-structures which is in a self-supporting and laterally stablecondition.
 7. A gantry crane as claimed in claim 1 in which at least oneend of said girder projects beyond the respective supporting column.